That's an interesting chart of offsets. I did an extensive frame accuracy test with FCP a few years back with a Kona2 or 3 and I found the video accuracy required the device to be set to Sony B not Sony A preset. The difference rolled the timeline one frame earlier relative to the record machine and made it possible to do proper insert edits. In the default Sony A the first frame of an insert edit would be doubled up because the sequence timeline in FCP rolled 1 frame late. I see most of your offsets are showing video 1 frame late which could be a by product of being in Sony A device preset. Did your tests involve Sony Machines and the Sony A vs. B presets in FCP? My tests did not involve any audio so I didn't check for that. Boy you'd think embedded audio would have to stay in sync kinda like VITC but I too have been told by AJA that some of the problems I found they were aware of and blamed a lot on QT.
--- In Avid-L2@yahoogroups.com, Mark Spano <cutandcover@...> wrote:
>
> Conversions with AJA hardware are notorious for ditching sync between audio
> and video. If you can spot it, you can compensate for it in sequence.
> Otherwise, do separate layoffs. This is with KONA, LH, iO, etc. - I do
> not rely on these to make conversions unless there's no audio involved. I
> did extensive testing a few years ago and posted my findings on the Cow and
> sent to AJA. They confirmed all of them. I made myself a cheat-sheet for
> them, for the KONA 3. Here it is:
>
> KONA 3 Output - Delay Compensation for Video Conversion
>
> When not performing any conversion on resolution or frame rate, the KONA 3
> is frame accurate in edit to tape for video and audio.
>
> --
> When upconverting (for example, 525i29.97 to 1080i29.97 - only resolution,
> not changing frame rate) the output from KONA 3 is frame accurate for audio
> and 1 frame late for video.
>
> To compensate for this, shift video in sequence earlier by one frame.
>
>
> When downconverting (for example, 1080i29.97 to 525i29.97 - only
> resolution, not changing frame rate) the output from KONA 3 is frame
> accurate for audio and 1 frame late for video.
>
> To compensate for this, shift video in sequence earlier by one frame.
> --
>
> --
> When converting (1080sf23.976 to 1080i29.97 - adding pulldown only, not
> changing resolution) the output from KONA 3 is frame accurate for both
> video and audio.
> --
>
> --
> When crossconverting (720p59.94 to 1080i29.97) the output from KONA 3 is
> frame accurate for video and audio is one field early in 29.97i.
>
> When downconverting (720p23.976 to 525i29.97) the output from KONA 3 is
> frame accurate for video and audio is one field early in 29.97i.
>
> When crossconverting (720p23.976 to 1080i29.97) the output from KONA 3 is
> frame accurate for video and audio is approximately .4 frame early in
> 29.97i.
>
> The only true solution to compensate for these types of conversions is to
> do a separate edit for video (at conversion) and audio (with no
> conversion), since audio can not easily be shifted accurately by less than
> a frame.
>
>
> On Wed, Apr 11, 2012 at 4:41 PM, Nigel Gourley <
> avid-l@...> wrote:
>
> > **
> >
> >
> > Hi there,
> >
> > Is this a "feature"..
> >
> > V6 with AJA card. HD sequence, using the secondary output as downconvert to
> > standard def. embedded audio output. The audio is probably 2 frames earlier
> > than the vision. And even if you switch the project to SD it's still out..
> >
> > I can understand there is a delay with the downconvert but I would expect
> > the pictures and sound to be the same..
> >
> > I can't see this on the web anywhere..
> >
> > Thanks
> >
> > N
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
>
>
> [Non-text portions of this message have been removed]
>
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